A Circle

Please finish the theory part before starting this exercise

The only math knowledge that you need to recall for now is sine and cosine and how they relate to the unit circle

A few more useful things:

  • sin and cos work in radians: so the range of one period (one rotation on the unit cycle) is 0...2π
  • in Processing you clear the canvas with background(255). If you do this only once (in the setup method) you can keep drawing frame by frame (like a drawing machine!)
  • to draw the dots you can use circle() or ellipse();

So to move along a circle you would have the following code

x = sin(angle) * radius;
y = cos(angle) * radius;
angle=angle + step;  // increase the angle each iteration

Draw a circle, frame by frame

  1. Fire up Processsing
  2. try (without looking at my code) to draw a larger circle made out of dots (a tiny filled circle)
  3. Do this by drawing one dot per frame

Your result should look somethinglike this: (Amazing!)

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